What is the test for a variation of an order where a party is seeking to change the existing order?

An application to vary is not an appeal of an original order, nor is it an opportunity to retry a prior proceeding. The existing order must be treated as correct as of the date the order was made. The existing order can only be varied if a party proves that a material change in the circumstances exists, and as a result of that change, the current order no longer meets the child's best interests: Gordon v. Goertz, 1996 CanLII 191 (SCC), [1996] 2 S.C.R. 27 (S.C.C.).

A material change is one which has not been foreseen or could not have been reasonably contemplated by the judge who made the original order: Gordon v. Goertz, supra. A material change must be more than a temporary or minor change. The change must be a substantial, continuing one which impacts the child and the ability of the care givers to meet the needs of the child.